Challenging behaviour is a label often given to people with learning disabilities when their behaviour challenges the system around them (Department of Health, 1993). There are numerous ways of understanding challenging behaviour. Given the mutual dependence between community learning disability teams and community support services in supporting people with learning disabilities, it was considered interesting to make explicit some of the ideas and assumptions that might enable or disable teams to work in consistent ways. This study draws on the research of Haydon-Laurelut, Nunkoosing and Millett (2014) and Nunkoosing and Haydon-Laurelut (2011).\ud \ud Six support workers at day centres for adults with learning disabilities (referrers) and six clinical psychologists working at community learning disability teams (responders) took part in semi-structured interviews. The interviews asked about their understandings of challenging behaviour in the context of making and receiving referrals. Interviews were transcribed verbatim and analysed using thematic analysis. \ud \ud Findings suggested that the support workers and clinical psychologists had quite similar ways of understanding challenging behaviour, which was an unexpected finding. They both used dominant discourses to talk about their understandings, as well as acknowledging that challenging behaviour is a social construction. These understandings were acknowledged to occur within the system or network around the person. Although there were shared understandings, still a schism existed in terms of how the services viewed each other. It was considered that something other than ‘understanding’ may be at the root of these differences and the suggestion made that the impact of emotions and relationships not being fully attended to and a common sense of powerlessness in the network could be important. \ud \ud Implications of the findings on an individual, service, policy and societal level were considered as well as ideas for future research. A critical review is provided in the final part of this thesis.